1. Field of the Invention
The present invention relates to an ink discharge apparatus which forms an image on a recording medium by discharging fine ink droplets from nozzles toward the recording medium such as a paper or the like.
2. Description of the Related Art
Conventionally, an ink discharge apparatus is known, which is exemplified by a printer apparatus based on the ink-jet system for forming an image on a recording medium by discharging inks toward the recording medium such as a paper or the like. Such an ink discharge apparatus includes a discharge head provided with nozzles for discharging the inks and ink cartridges accommodating the inks. The ink discharge apparatus discharges the inks supplied from the ink cartridges, from the nozzles of the discharge head.
The ink discharge apparatus as described above is provided with a discharge performance restoring mechanism in order to maintain the ink discharge function or the ink discharge performance of the nozzles. The discharge performance restoring mechanism is provided, for example, in order that the dust, the dried inks, and the bubbles, which exist in the discharge head, are removed when the maintenance is performed or the inks are initially charged into the discharge head. The discharge performance restoring mechanism includes, for example, a cap which covers a plurality of nozzles that are open on a nozzle surface of the discharge head, a suction pump which is connected to an ink discharge port formed through the cap via a connecting tube and which generates the negative pressure in the space formed between the cap and the nozzle surface, and a waste ink tank which is connected to the suction pump and which recovers the sucked waste ink.
The discharge performance restoring mechanism as described above performs the “capping operation” in which the nozzle surface of the discharge head is covered with the cap, it performs the “purge operation” in which the suction pump is operated to recover the waste ink from the discharge head, and it performs the “cap release operation” in which the cap is separated from the nozzle surface.